Thermostatic valve for incubators



(No Model.)

' M. T. GREENLEAF.

THBRMOSTATIG VALVE EUR INGUBATORS. Y 8 No. 388,666. Patented Aug. 28,1888.

N PETERS mwuumgnphur. wamngla. im:4

detail view of the thermostat detached.

UNITED STATES PATENT OEEIcE.

MILLER T. GREENLEAF, OF QUINCY, ILLINOIS.

THERMOSTATIC VALVE FOR INCUBATORS.

SPECIFICATION forming part of Letters Patent No. 388,666, dated August 28, 1888.

Application tiled November 22, 1887. Serial No. 255,899. (No model.) I

Illinois, have invented new and useful In1` provements in Incubators, of which the following is a specification. 4

My invention relates to incubators for the artificial hatching of poultry; and the pur-l pose thereof is to provide an extremely simple device for automatically regulating and preserving the temperature of the interior of the hatching-compartment.

It is also my purpose to provide means whereby t-he automatic apparatus may be adjusted to act at any predetermined point within certain limits, the whole being of uniform and certain operation, not liable to derangement, and of sensitive and exact action.

The invention consists in the several novel features of construction and new combinations of parts, hereinafter fully set forth, and specilcally pointed ont and defined in the claims.

In the accompanyingdrawings, Figure 1 is a sectional view illustrating my invention. Fig. 2 is a plan view of the same. Fig. 3 is a Fig. 4 is a detail view ofthe ventilatorplate, showing the manner of balancing the same.

In the said drawings the referencefnumeral l denotes one ofthe hatching-compartments of an incubator of any ordinary construction, save as to those points hereinafter described. Closing the top of this compartment is a ventilator-plate, 2, which may be centrally hung upon a pivot or transverse rock-bar; but I prefer to support the plate upon a bar, 3,which is triangular in cross-section, the ends resting upon the acute angle of the triangle and forming practically knifeedge bearings. These bearings rest upon suitable stationary snp` ports, 4, forming part of the frame.

Surrounding the ventilator 2 and rising to a suitable height is a screen-wall, 5, which prevents the plate from being deiiected by accidental currents of air. l

Mounted in any suitable manner upon the top of the compartment 1, whereby it may have longitudinal adjustment, is a plate or support, 6, arranged upon one side of the ventilator-plate 2. Attached thereto in the manner to be described is the ther-mostat consist ing of a plate of brass and a bar or wire of steel laid thereon and fastened thereto between the ends of said plate by soft solder. The parts are then' bent into circular\form,the steel wire being outside and looped over the end of the' brass plate, as shown at 7, to retain the parts in the proper relative position. From the loopthe wire passes upward, and its end 8 is bent to bear against the upper angle of one of the ends of the knife-edge 3. The other end of the thermostat is brought into proximity to the support 6, which is so mounted upon the top of the hatching-compartment as to have alimited longitudinal movement. When exposed to heat, the unequal expansion of the two metals causes the circular plate and wire to straighten, or tend to straighten, thereby causing the point 8 to bear against the knife-edge bearing and tilt the ventilator, thereby permitting the escape of a portion'of the heated air contained therein, the place thereof being supplied by cooler air. When the temperature is reduced sufficiently, the contraction of the metals causes the ends of the thermostat to draw together and resume their former position, whereon the valve closes by gravity, a light weight, 9, being placed on one end for that purpose. i

Upon the support 6,1 form a lng,10,agains which a set-screw, 11, has bearing, to give adjustment to the support toward or from the knife-edge bearing, on which the end 8 of the thermostat rests. By operating this screwy the parts may .be so adjusted that the thermostat will swing the ventilator at a higher or lower temperature, as circumstances may require,

'the points of action relatively to the thermo- IOO side of the plate 2, a lead ball, 9, having a slot, is placed upon the strip Il andmoved along,` until the proper balance is ascertained, when it is soldered in place. By this method I am enabled t0 balance a great number of plates in a very short time.

I may use any two metals having different indices of expansion in place of brass and steel, as it is evident that many other substances would accomplish the same result.

What I claim is- 1. In an incubator, the combination, with a box or hatching-compartment having a ventilator-plate mounted upon a central axis having knifeedge bearings, of a thermostat com posed of two metals of different expansibility curved into circular form, one end of said thermostat being rigidly mounted upon the top of the compartment and the free end bearing against the top of one of the knife-edge bearings, substantially as described.

2. In an incubator, a ventilatonplate having' central knife-edge bearings, a thermostat composed of' brass and steel or other metals having different-indices of expansion bent into nearly circular form, au adjustable support, to which one end of said thermostat is rigidly fastened, and a set-screw for adjusting said support to bring its free end nearer to or farther from the knife-edge bearing, substantially as described.

3. A ventilator-plate having,` a bracket attached, provided with a strip of metal lying lengthwise of said plate and at right angles to its surface, and a ball straddling said strip and soldered thereto, substantially as described.

4. A Ventilatorplate having` a bracket consisting of a strip, 12, having oppositely-ex tending` pieces 13 soldered on one surface of the ventilator-plate, and a ball, 14, straddling the strip and soldered thereto, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

M. T. G BEEN LEAF.

Vit n esses:

JAMES L. Noams, J. A. RUTHERFORD. 

